Most of the conventional awnings are of the fixed type which may be classified into three categories, i.e. a one side type, a four-corner supporting type, and a two sloping side type. However, none of these types are adjustable. At most, the height of these may be adjusted. Since they are of the fixed structure, they are unable to meet the requirements of a travelling user, such as the ability to be set up, shipped and stored, etc. There is a sun umbrella recovered which can meet the aforesaid requirements, but its shading and covering area is limited as a result of its mechanical structure; in other words, it can not be used for covering a larger area because of its insufficient support structure.